S-90311A164 1/4"-20 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Vibration-resistant secure fastening with nylon patch thread locker that maintains integrity across industrial temperature ranges (-50° to 250°F)
• Superior corrosion resistance through 316 stainless steel construction for demanding chemical and marine environments
• Precision alignment and bearing surface with 5/16" shoulder diameter and 3/4" shoulder length maintaining tight tolerances
• High-strength performance delivering 70,000 psi tensile strength and 35,000 psi shear strength for critical applications
• Secure installation and removal with knurled socket head design providing enhanced grip during torque application
• Interchangeable compatibility with UNC coarse threading and Class 3A fit ensuring precise engagement with mating components
• Regulatory compliance assurance meeting ASME B18.3 specifications while being RoHS 3 and REACH compliant

Professional Applications & Engineering Value

Engineered for precision machinery and industrial applications requiring reliable rotational and linear motion control, this 1/4"-20 UNC shoulder screw solves critical alignment challenges. The 316 stainless steel construction provides exceptional resistance to corrosive environments while maintaining structural integrity under continuous load. The integrated nylon patch thread locker prevents loosening from vibration in equipment such as robotic arms, conveyor systems, and precision instruments. With its Class 3A thread fit and precisely machined shoulder, this component ensures accurate positioning of gears, pulleys, and rotating assemblies while the knurled socket head facilitates secure installation in confined spaces. The combination of high tensile strength and controlled shoulder dimensions makes it ideal for applications demanding both mechanical strength and dimensional stability.

Specification Summary & Compliance

This shoulder screw features 1/4"-20 UNC coarse threading with Class 3A thread fit for precision engagement. Critical dimensions include shoulder diameter of 5/16" (tolerance: -0.004" to -0.002") and shoulder length of 3/4" (tolerance: -0.005" to 0.005"). Manufactured to ASME B18.3 specifications with material hardness of Rockwell B79. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring suitability for global industrial applications.